1. Field of the Invention
The present invention relates to fire escapes and more particularly pertains to an emergency cable descent system for lowering a person from a building in an emergency situation.
2. Description of the Prior Art
The use of fire escapes is known in the prior art. More specifically, fire escapes heretofore devised and utilized for the purpose of assisting persons in escaping from a building are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
For example, a fire escape with a cable reel brake is illustrated in U.S. Pat. No. 4,602,699 which utilizes a housing containing a rotatable cable drum therein with a cable connected thereto and extending from the housing for connection with a supporting structure. The housing may be connected to a person descending from an upper floor of a building or the like during an emergency situation such as a fire. An automatic brake mechanism controls the rate of descent of such a person by applying a braking force to a rotatable component geared to the cable drum for controlling unreeling movement of the cable.
An emergency descending device is disclosed in U.S. Pat. No. 5,060,758 which comprises a rotary wheel and a cam mounted between a pair of side plates with a main rope passing between the rotary wheel and the cam. A rotation of the rotary wheel caused by the main rope generates a centrifugal force on a brake shoe, thereby causing a rotation of a brake drum. The rotation of the brake drum pivots the cam towards the rotary wheel, thereby clamping the main rope therebetween to provide a suitable descending speed.
Another patent of interest is U.S. Pat. No. 4,729,454 which describes a self braking safety apparatus for the rapid descent of persons in cases of emergency. The apparatus can be secured to a fixed point from which the descent is to be made and comprises a rotor on which a rope is wound mounted coaxially of a drum. A heat resistant handle and a brake which can be actuated by the user are secured to the drum by brackets. The brake may be utilized to stop the device and when the hand brake is released, the rotation of the rotor and the centrifugal force generated thereby exert a braking action against the inner surface of the drum to produce a constant descent speed of about 2.5 m/sec.
Other relevant documents include U.S. Pat. No. 4,949,812, and U.S. Pat. No. 4,485,893.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not describe an emergency cable descent system for lowering a person from a building which includes a boom that may be pivoted outside a window of a building to support a cable away from the exterior of the building, whereby the person may be lowered from the building at a safe distance therefrom. Furthermore, none of the known prior art fire escapes teach or suggest a cooperating mechanical siren for alerting other occupants of the building to a use of the system.
In these respects, the emergency cable descent system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of lowering a person from a building in an emergency situation.